This invention is directed generally to methods for generating electricity from bacterial culture.
Generation of power from non-traditional sources is a desirable goal. In recent decades, it has become increasingly necessary to find a non-toxic, efficient, renewable and cost-effective alternative energy resource. This is because non-renewable resources such as oil are being depleted at an alarming rate. The search for the ideal energy resource has led to the development of various power supplies including Aeolian, hydro, nuclear, and biomass. However, these resources, although renewable, are either inefficient (wind power), or potentially hazardous (nuclear energy).
Electricity can be produced through the principles of electromagnetism. For example, a horizontally spinning magnet suspended in a copper coil generates a magnetic field, aligning the atoms of the coil with common poles. Electrons in the copper coil atoms begin to flow through the coil, because of the polar gradient, inducing electric current.
In 1975, bacteria of the genus Aquaspirillum were found to have magnetic properties which they use to travel along the earth's magnetic field lines, towards lower oxygen concentrations. These unique properties were labeled as magnetotaxis. In 1979, Blakemore, D. Maratea and R. S. Wolfe collaborated to isolate and form a pure culture of a freshwater magnetic spirillum (strain MS-1) in a chemically defined growth medium.
In 1991 K. Schleifer et al. proposed a new genus species name for the magnetic spirilla bacteria. Magnetic bacteria are shown to respond to increased levels of toxic materials such as acetone and propanol. These bacteria respond by decreased motility and magnetic field strength. Yang et al., in 2001 discovered that enhancing the growth medium with peptone, yeast extract, L-cystine and more succinic acid decreased the lag phase before bacterial growth.
In 2002, D. Schiller studied the benefits of biomineralization of magnetosomes from gryphiswaldense. Biomineralization is the process by which a bacterium forms magnetite crystals enclosed in a membrane in its body. D. Schultheiss et al., (2004) found that inactivating the flagella of magnetic bacteria resulted in mutants that were not magnetotactic (magnetic, but cannot move along the magnetic field lines of the earth).
Another discovery concerning this bacterium was in 2005 (Amemiya et al.) who found that the magnetic particles in the bacteria can be used in immunoassays and in DNA detection systems.